The marketing consultant’s death came just six weeks after he had received training in how to deal with engine failure.

“It couldn’t have been more pertinent,” said Mr McLaughlin. Three months earlier, the father-of-two had a medical which concluded that he was in good health.

His wife, Joy, described him as being in ‘excellent general health’. He was also described as ‘alert and sensible’.

Mr McLaughlin told her: “Your heart must be close to breaking. I know that inquests can churn up raw emotions.”

The jury heard investigators from the Air Accident Investigation Branch (AAIB) raised concerns about the stiffness of the valve following its examination.

Adrian Cope, who has 17 years’ experience, said it was ‘very stiff to turn’.

The two-seater Piper PA38 Tomahawk was built in 1978 and is now out of production.

Jeff Nuttall, managing director of Liverpool-based flying school Ravenair, which owned the aircraft, said it was ‘not unusual to have an aircraft for 45 years’ and noted that a plane’s life is determined by the number of hours flown, rather than age.

There are no regulations as to how stiff a fuel valve should be.

The jury concluded that the aircraft was ‘serviced in accordance with a service letter’ and had passed inspections.

After the inquest, a Ravenair spokesman said the firm had complied with all regulatory and maintenance issues. He said Ravenair hoped to provide the Daglish and McNicholls families with some closure.

He added: “Ravenair’s priority has been to understand the cause of this unfortunate incident, so as to ensure – as far as possible – no possible recurrence in the future.”

The spokesman said they did not believe the most probable cause had been established.